Compressor cooling system



Feb. 22, 1938. B, 's MKMAN 2,108,785

I COMPRESSOR COOL ING SYSTEM Filed April 1]., 1955 Q! n- 1 1 16 a i qINVI INTOR BUHTDN 5. All" MAN ATTORNEY Patented Feb. 22, 1938 UNITEDSTATES PATENT OFFICE COMPRESSOR COOLING SYSTEM Application April 11,1936, Serial No. 73,854

8- Claims.

This invention relates to fluid compressors, and more particularly to acooling system for a fluid compressor.

The principal object of my invention is to provide improvedmeans forcirculating a cooling fluid, such as water, through suitable coolingchambersof a compressor, and for controlling the temperature of saidfluid.

Another object of my invention is to provide an improved circulatingfluid cooling system for 'a compressor, having means for automaticallydraining the cooling fluid from exposed portions of the system when thecompressor is inoperative, so as to avoid the possibility of freezing.

In the accompanying drawing, the single figure is a diagrammaticsectional view of a fluid compressor showing associated therewith acooling system embodying my invention.

As shown in the drawing, a cooling system is provided for cooling acompressor I, said system comprising a lower supply reservoir 2, acooling manifold pipe 3, an upper reservoir 4 and an auto-- maticdraining valve mechanism 6 associated with said upper reservoir. Thecompressor l, which is adapted to rest on a floor or foundation 1, maybe of any suitable design having the usual inlet and discharge valvescontrolling the flow of fluid to and from a compression chamber, and asillustrated comprises a cylinder casing 8 having a compression chamber9, and a fluid compressing piston l mounted to reciprocate therein,which piston may be operated in the usual manner through the medium of acrankshaft (not shown). A cooling chamber II is formed within thecylinder casing 8 and surrounds the compression chamber 9.

The lower supply reservoir 2 is disposed below the level of the coolingchamber ll of the compressor I, being preferably buried beneath thefrost line or otherwise protected from freezing temperatures, and isprovided with a normally closed filling tube l2, through which water orother cooling liquid is initially supplied to the reservoir, said tubeopening into said reservoir below the upper wall thereof so as to limitthe level to which the reservoir may be fllledwith the cooling liquid.

In order to subject the cooling liquid in the reservoir to fluid underpressure, a pipe i3 is provided, the lower end of which is connected tosaid supply reservoir above the level of the cooling liquid therein, andthe other end of which communicates with a port M formed in the cylindercasing 8 and opening into the compression chamber 9. The location'of theport l4 intermediate the limits of travel orstroke of the piston I0 issuch as to permit said port to remain open while the piston is moving onits compression stroke until the pressure desired for operation of thecooling system has been built up in chamber 9, the further movement ofthe piston then operating to close the port. It will be understood thatonly a part of the fluid compressed in chamber 9 will flow through thepipe i3 to the reservoir 2, the communication between the chamber andpipe being cut off when piston l0 blanks port I4. A ball check valve I6is interposed between the pipe l3 and the port It for preventing backflow of fluid under pressure from said pipe to the compression chamber.

Extending into the supply reservoir 2 below the level of the coolingliquid therein is a supply pipe H, which leads to the cylinder casing 8of the compressor and is connected through a passage 8 with the lowerportion of the cooling chamber I I. The upper portion of the coolingchamber ll is connected by way of a passage 2l-with the lower end of thecooling manifold pipe 3, the other end of said pipe being connected withthe upper reservoir d.

A casing 22 is secured to the reservoir 4 and I carries the automaticdraining valve mechanism 6, comprising a member 25 having valves 23 and24 at its opposite ends, which are slidably mounted in suitable bores insaid casing, the valve 23 being adapted to control communication fromthe reservoir 4 by way of passages 21 to the atmosphere and the valve 24being adapted to control communication from said reservoir to adischarge pipe 29 which leads to the lower supply reservoir 2. The valve2 has a restricted passage Zta for permitting gradual equalization ofthe pressures on opposite sides thereof when the compressor isinoperative, as hereinafter more fully described. I

For operating the valves 23 and 24 a toggle lever mechanism is providedcomprising oppositely extendingv levers 30 and 3!, the adjacent ends ofwhich are pivotally mounted on a pin 32, which is carried by 9. lug 33on the casing 22 which projects into the reservoir 4. A spring34connects together the outer ends of said levers. The lever 30 has aslotted portion 36 intermediate its ends for receiving a reduced portionof the member 25 intermediate the valves 23 and 24, said intermediatereduced portion providing shoulders adapted to be engaged by the portion36according to the position of the lever 30. The lever .3! extends intothe reservoir 4 and carries a float 38, which normally maintains thevalve mechanism manner by the compressing piston I is supplied throughthe port l4, past the check valve I6 and through pipe I 3 to the supplyreservoir 2 at a. faster rate than it can escape by, way of the pipe 29and the restricted passage 240.. As a result, a fluid pressure is builtup in the rservoir 2 which acts on the body of the liquid therein sothat liquid from said reservoir is forced to flow through the pipe I! tothe cooling chamber ll of the compressor casing 8, thereby cooling thecompressor. The cooling liquid having thus circulated through thecooling chamber in the. cylinder head is then forced upwardly throughthe cooling manifold pipe 3, whereby most of' the,

heat absorbed from the compressor is dissipated, and from said coolingpipe the liquid flows into the upper reservoir 4. 1

As the level of cooling liquid rises in the upper reservoir 4, the float38 is moved upwardly, turning the lever 3| of the toggle lever mechanismabout the pin 32 and causing the spring 34 to be stretched, the lever 30remaining stationary due to its engagement with the seated valve 24.When the lever 3| and spring 34 are thus moved beyond the position inwhich the levers 30 and 3| are in alignment, said spring is then sopositioned relatively to the levers, that it exerts its force so as totend to pull the end of lever 30 in an upward direction, since the lever3| is-positioned by the weight of the float 38. This movement will thuscause the force of the spring to move the lever 30 with a quicksnap-like action, so that the portion 36 engages the upper shoulder ofthe' member 25 and thereby quickly moves the valve 23 to its seatwhileunseating the valve 24.

The valve 23 thus closes the atmospheric communication and the valve 24establishes communication for effecting rapid equalization of the fluidpressure in the supply reservoir 2 with that in the upper reservoir 4,so as to permit cooling liquid to flow from said upper reservoir throughthe discharge pipe 29 into the supply reservoir. When the level of theliquid in the upper reservoir 4 has been lowered sufficiently, the float38 will operate the toggle lever mechanism so as to return the valve 24to its seat and unseat the valve 23, thereby venting said reservoir inorder to per- .mit continued flow thereto of cooling liquid forced fromthe manifeld pipe '3, as already described. en operation of thecompressor 1 is stopped, the fluid under pressure bottled up in thespace above the cooling liquid in the supply reservoir 2 and in thedischarge pipe 29 is permitted gradually to flow through the restrictedport 24a in the valve 24 to the upper reservoir 4, and as equalizationof the fluid pressures in said reservoirs is thus effected, the coolingliquid will drain from the upper reservoir downwardly through thecooling pipe 3, the cooling chamber II in the compressor, and throughthe pipe I! into the lower supply reservoir. v 7 It will thus be seenthat my invention provides an efficient and economical compressorcooling system having improved means for effecting the circulation ofcooling liquid therethrough during operation of the compressor, andconstructed and arranged to permit the cooling liquid to beautomatically drained from the system when said compressor is idle, soas to prevent freezing of the liquid.

While one illustrative embodiment of the invention' has been describedin detail, it is not my intention to limit its scope to that embodimentor otherwise than by the terms of the appended claims.

Having now described my invention, what I claim as new and desire. tosecure by Letters Patent, is:

1. The combination with a fluid compressor having a. cooling chamberthrough which cooling liquid may flow for cooling the compressor, of asupply reservoir adapted to contain a supply of cooling liquid andhaving a communication through which liquid from the reservoir issupplied to said chamber, a second reservoir communicating with saidchamber into which flows liquid supplied to said chamber, means forsubjecting liquid in said supply reservoir to the pressure of fluidsupplied by the compressor and means operative upon a predeterminedincrease in the supply of liquid in the second reservoir for drainingliquid from the second reservoir into the supply reservoir.

2. The combination with a fluid compressor having a chamber throughwhich cooling liquid may flow for cooling said compressor, of a coolingliquid supply reservoir communicating with said chamber, a secondreservoir communicating with said chamber, valve means controllingcommunication from said second reservoir to said supply reservoir, meanscontrolled according to the level of liquid in the second reservoir foroperating said valve means, and means for supsubjecting cooling liquidin said supply reservoir to the pressure of fluid compressed by thecompressor for forcing liquid from said supply reservoir through saidchamber into said second reservoir.

4. The combination with a fluid compressor having a chamber throughwhich coolingjiquid may flow for cooling said compressor, of a coolingliquid. supply reservoir communicating with said chamber, a secondreservoir communicatin -with said chamber, an exhaust valve controllingcommunication from said second reservoir to at mosphere, a drain valvecontrolling communication from said second reservoir to said supplyreservoir, 9. float in the second reservoir, means including a togglemechanism operable by said float upon a rise in the level of liquid inthe second reservoir for opening the drain valve and closing the exhaustvalve and upon a fall in the level of liquid for closing the drain valveand opening the exhaust valve, and means for supplying fluid underpressure to said supply reservoir for forcing cooling liquid therefromthrough said chamber into said second reservoir.

5. The combination with a fluid compressor having a cooling chamberthrough which cooling liquid may flow, of a supply reservoir below saidchamber adapted to'contain cooling liquid, means for supplying fluidunder pressure to said supply reservoir, a. communication through whichcooling liquid is forced from the supply reservoir through the coolingchamber by said fluid under pressure, an upper reservoir disposed aboveand communicating with said cooling chamber, a conduit connected to theupper reservoir and the supply reservoir, and valve means controlled bycooling liquid forced into said upper reservoir for effecting gravityflow therefrom of cooling liquid to said supply reservoir.

6. The combination with a fluid compressor having a chamber throughwhich cooling liquid may flow for cooling said compressor, of a coolingliquid supply reservoir below said chamber and communicating therewith,an upper reservoir communicating with said chamber, means for supplyingfluid under pressure to said liquid supply reservoir during operation ofthe compressor for forcing cooling liquid from the supply reservoirthrough the chamber into said upper reservoir, and a restricted passagecommunicating with the liquid. supply and upper reservoirs adapted topermit equalization of the fluid pressures therein for effectingdrainage of cooling liquid from said upper reservoir to said liquidsupply while the compressor is inoperative.

7. The combination with a fluid compressor having a chamber throughwhich cooling liquid may flow for cooling said compressor, of a coolingliquid supply reservoir below said chamber and communicating therewith,an upper reservoir communicating with said chamber, means forcommunicating fluid pressure to the liquid supply during operation ofthe compressor for forcing cooling liquid therefrom through the chamherinto the upper reservoir, valve means operative to establishcommunication for permitting flow of cooling liquid from said upperreservoir to said cooling liquid supply, and means for relieving saidliquid supply from fluid pressure when the compressor is inoperative, topermit cooling liquid to drain from the upper reservoir and said chamberto the liquid supply.

8. The combination with a fluid compressor having a cooling chamberthrough which cooling liquid may flow for cooling the compressor, of asupply reservoir containing cooling liquid and having a communicationthrough which liquid is supplied to said chamber, means for subjectingthe liquid in said reservoir to fluid pressure for forcing liquidtherefrom into said chamber, cooling means communicating with saidchamber and adapted to receive and to cool liquid forced therethrough,and valve means operative by liquid supplied from the reservoir throughthe chamber to the cooling means to establish communication between saidcooling means and said reservoir, whereby return flow of liquid to saidreservoir may be effected. 1

BURTON S. AIKMAN.

